RFIDRFIDRadio Frequency Interference Detection ?

I.U.C.A.F. Summer School

May / June. 2010

RFIDRadio Frequency Identification

Use of a device = RFID Tag attached to an object, animal or even a person, for the purpose of

identification and tracking using radio waves.

Bar-codes

RFID tags have 2 parts:1) Integrated circuit for storing &

processing information, and modulating /demodulating an RF signal.

2) An antenna for receiving and transmitting the signal

Types of Tags.

a) Passive – no battery & require external source of power

b) Active – have battery & can transmit autonomously

c) Battery assisted Passive ( BAPs) – need external source to ‘wake them up’, but then transmit. These tend to have higher ‘gain’ & therefore greater range

RFID tags have 2 parts:1) Integrated circuit for storing & processing

information, and modulating /demodulating an RF signal.

2) An antenna for receiving and transmitting the signal

History.

Grew out of Russian Espionage. ( 1945 ) ?

Leon Theremin devised a listening device which had the essentials of RFID. It re-transmitted incident radio waves with audio information

Actually, similar technology was invented in 1915 in the U.K., called an IFF transponder, which was used by aircraft to identify whether they were ‘friend’ or ‘foe’.

First Patent was granted in the U.S. – also in 1945

1983:First Patent using the abbreviation RFID was by Charles Walton in the U.S.

1973:Mario Cardullo developed a passive radio transponder which had a 16-bit memory.i.e. powered by the interrogating signal. He demonstrated it to the New York Port Authority. He also listed lots of possible uses.Shipping, Toll roads, Animal Identification etc.

Before the end of 1973, ‘reflected power’ ( = modulated back-scatter) RFID tags, both passive and semi-passive had been demonstrated. There was a portable system operating at 915 MHz which used 12-bit tags.

This is still used by a majority of today’s UHF ID tags.

The U.S. Department of Defence has millions of them !!

Original Tags were inductively coupled.

‘Magnetic Field’ of reader was used to read.

Capacitively coupled tags created in an attempt to lower the costs. ( Meant to be disposable ). These tags used conductive Carbon ink instead of metal coils to transmit data.

However, they did not really ‘catch on’.

Great improvement on Barcodes because the Tags have a read & WRITE capability. Data on the tags can be changed, up-dated and ‘locked’.

Antenna receives signal from reader;

Either using own battery or power from incoming signal, tag sends signal to reader.

Reader decodes the signal.

Active and semi-passive tags ‘broadcast’ – usually reserved for costly items that are read over fairly long distances.

Their frequency range is often ~850 to 950 MHz.

With higher power batteries, range can be ~100 m.

Radio frequencies used:-

0.125 to 0.1342; 0.140 to 0.1485; 13.56 & 840 to 960 MHz.

Now starting to use 333 THz, 380 THz and 750 THz

‘Awkward’ antennas of RFID can be replaced with photo-voltaic components and IR-Leds on the ICs.

Tags can be read from a few millimetres to distances beyond the line of sight, dependent upon the transmitter and ‘receiver’ (= reader )

Three Storage types:a) Read / Writeb) Read Onlyc) Write Once / Read Many = WORM

WORMS can have data added, but not overwritten

Newer innovations include active, semi-active and passive tags which can store up to 2kbytes of data

(a micro-chip + antenna ( + battery ))

Components are enclosed within plastic, silicon or sometimes glass

In 2008, more than a dozen new UHF RFID tags were developed to be mounted on metal.

THIS YEAR, three key factors have resulted in a significant increase in RFID use.

1) Decreased cost of equipment and tags

2) Reliability approaching 99.9%

3) “Stable” international standard for use at UHF frequencies.

Expected cost of a passive UHF RFID tag in 2011 is ~3 U.S. cents

International Organisation for Standardisation ( ISO )

Non-governmental: Founded in 1947 with Headquarters in Geneva.

Composed of various National Standards Organisations

and is nowadays very influential.

Every product must have a unique product code.

Electronic Product Code identifiers are being developed (EPCs).

Information to be stored in chips in Product Markup Language (PML), based upon XML.

PML would allow computers to communicate with any computer system and, by extension, to Web pages.

Fourth factor !! The size of Tags

A Silicon on Insulator (SOR ) process has been used to manufacture dust-sized chips which can store 38-digit numbers using a 128 bit ROM.

Hitachi holds the record for the smallest chip – 0.05 x 0.05mm

A researcher at Bristol University in the U.K. has successfully glued micro-transponders to live ants !

Major challenge – antenna attachment !

Examples of Tag Uses

Toll Roads.Sydney Harbour Bridge; Gt. North Road Tunnel in NZ; Singapore Highways, where tolls are adjusted dependent upon traffic

Product Tracking.UHF Tags for packing cases, pallets, shipping containers, lorries & trailers. ( In Jan. 2005, Walmart insisted that all its suppliers had to have RFID labels on shipments.)High-Freq Tags for books, jewelry, airline baggage, pharmaceuticals, apparel.(Emirates have started a baggage trial at Heathrow & Dubai )

Animal Identification

People Identification – most disturbing.

Ice Cream !

People Tagging.

Some people have been tagged, with their tags including their Medical Records.

Tag athletes in London or New York Marathons ?

Animal Tagging is already in considerable use.

Ear tags & implants.

Problems with tagging humans & bio-passports !

Skimming & Eavesdropping – identity theft.

Bio-passports are expensive, but installing readers at all airports will be staggeringly expensive !

Why UWB for RFID?

• Over 7.5 GHz (3.1 – 10.6 GHz) of unlicensed spectrum available under Part 15 rules as of February 14, 2002

• MSSI PAL650 tagging system approved for unlicensed use on July 31, 2003

• UWB tags have distinct advantages over other RFID solutions

MSSI UWB Performance Advantages

• Range (600 feet under LOS conditions)

• Real time tracking to within 1 foot

• Reliable tag reading in metallic & densely packed environments

• Low primary power

• Small size

• Low cost

Tag Range Comparison

0 100 200 300 400 500 600 700

MSSI UWB

Active

Passive

Tag

Type

Feet

MSSI Active Tag Progress

L-Band

C-Band

1”x1”

0404

MSSI PAL650 Evaluation Kit• FCC Certified for Unlicensed Use

•1 foot tracking resolution

• 4 year battery life

• 40,000 Sq. Ft. Coverage Area

• Price $29,995

MSSI PAL650 Customer Applications

• Hospital asset and personnel tracking• Engine tracking• Robotic vehicle tracking• Navy shipboard personnel tracking• Sheet metal factory process control • Soldier tracking• Animal tracking• Firefighter/First Responder tracking